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What happens if you have a blood clot in your leg?

What happens if you have a blood clot in your leg?

Navin Khosla NowPatientGreen tick
Updated on 13 May 2024

Blood clots can be a silent and potentially deadly threat, especially when they develop deep within the veins of the leg. Known as deep vein thrombosis (DVT), these clots form when blood thickens and coagulates in a blood vessel blocking the flow of blood. While DVT’s may not be immediately life-threatening, the real danger lies in the possibility of the clot breaking free and traveling to the lungs, causing a pulmonary embolism, a condition that can be fatal if not treated promptly.

Understanding the symptoms, risk factors and prevention strategies for deep vein thrombosis is crucial, as early detection and proper management can mean the difference between a positive outcome and a life-threatening situation. In this guide, we will delve into the details of DVT’s, providing you with the information on how to recognize warning signs, how to take proactive steps to reduce your risks and how to seek timely medical help or interventions, if needed.

What is Deep Vein Thrombosis (DVT)?

Deep vein thrombosis, or DVT, is a blood clot that forms in a vein deep within the body, most commonly in the lower leg. These clots develop when the blood thickens and coagulates, partially or completely blocking the flow of blood through the affected vein. While DVT can occur in various parts of the body, including the arms, abdomen, or brain, the vast majority of cases (around 80%) involve the lower limbs.

Understanding the dangers of DVT

Even though DVT itself is not immediately life-threatening, the real danger lies in the potential for the clot to break free and travel through the bloodstream to the lungs, a condition known as a pulmonary embolism (PE). A pulmonary embolism can be a life-threatening emergency, as it can obstruct blood flow to the lungs and impair the delivery of oxygen to vital organs.

In addition to the immediate threat of a pulmonary embolism, DVT can also lead to long-term complications, such as post-thrombotic syndrome. This condition occurs when the damage caused by the blood clot to the valves and inner lining of the veins leads to chronic leg pain, swelling, discoloration, and even the development of venous ulcers.

Prevalence and risk factors

Deep vein thrombosis is a relatively common condition, affecting approximately 1 to 3 out of every 1,000 adults each year in the United States. The risk of developing DVT increases with certain factors, including:

  • Age: The risk of DVT rises with age, especially after the age of 60
  • Obesity: Excess body weight is a significant risk factor for DVT
  • Immobility: Inactivity for long periods of time, such as during hospitalization or bed rest, a long flight or recent surgery can increase the risk of clot formations
  • Certain medication: Birth control pills (oral contraceptives) or hormone replacement therapy can both increase the risk of blood clots
  • Pregnancy and the postpartum period: Hormonal changes and increased pressure on the veins during pregnancy and the weeks following childbirth can elevate the risk of DVT
  • Cancer and its treatments: Certain types of cancer and cancer therapies, such as chemotherapy can increase the likelihood of developing blood clots
  • Inherited blood clotting disorders: Genetic conditions that affect the body’s ability to regulate blood clotting can predispose individuals to DVT
  • Previous history of DVT: Individuals who have experienced a DVT in the past or those with a strong family history of blood clots are at a higher risk of developing another one

Symptoms of DVT

The symptoms of deep vein thrombosis can vary, and in some cases, the condition may not present any obvious signs at all. However, the most common symptoms of DVT include:

Leg symptoms

  • Swelling in the affected leg, often sudden and localized
  • Pain or tenderness in the leg, which may be more pronounced when standing or walking
  • Warmth and redness in the area of the leg where the clot is located
  • Visible enlargement of the veins near the skin’s surface

Other symptoms

  • Abdominal pain (when the clot affects the veins in the abdomen)
  • Severe headache and/or seizures (when the clot affects the veins in the brain)

It’s important to note that up to 30% of people with DVT may not experience any symptoms at all, making the condition particularly challenging to detect. Additionally, some individuals may not recognize the severity of their symptoms, dismissing them as minor discomfort or overlooking them entirely.

Diagnosing DVT

If your healthcare provider suspects you may have deep vein thrombosis, they will typically begin with a physical examination and review of your medical history. This initial assessment can provide valuable clues about the potential presence of a blood clot.

Imaging Tests for DVT Diagnosis

To confirm the diagnosis of DVT, healthcare providers will typically order one or more of the following imaging tests:

  • Duplex venous ultrasound
  • Venography
  • Magnetic Resonance Imaging (MRI) or Magnetic Resonance Venography (MRV)
  • Computed Tomography (CT) Scan

In some cases, healthcare providers may also order specialized blood tests to determine if the patient has an inherited or acquired blood clotting disorder that may have contributed to the development of the DVT.

Treatment for DVT

The primary goals of DVT treatment are to prevent the clot from growing larger, stop it from breaking off and traveling to the lungs, and to reduce the risk of future blood clots. The specific treatment plan will depend on the individual’s circumstances, the location and severity of the clot, and any underlying medical conditions.

Anticoagulant medications

The core of DVT treatment is the use of anticoagulant or blood-thinner medications. These drugs work by making it harder for the blood to clot, which helps to prevent the existing clot from growing larger and reduces the risk of new clots forming.

Some common anticoagulant medications used to treat DVT include:

  • Warfarin
  • Heparin
  • Rivaroxaban
  • Apixaban
  • Edoxaban

Patients may need to take these medications for several months, or in some cases, indefinitely, depending on their risk factors and the severity of their condition.

Compression stockings

In addition to anticoagulant medications, healthcare providers may also recommend the use of compression stockings to help manage the symptoms of DVT and prevent long-term complications. These specialized stockings apply gentle, graduated pressure to the leg, which can help reduce swelling and improve blood flow.

Invasive treatments

In some cases, when the DVT is extensive or the patient is unable to take anticoagulant medications, healthcare providers may recommend more invasive treatments, such as:

  • A procedure involving a catheter to deliver clot-dissolving medications directly to the site of the blood clot
  • A technique using a specialized device to physically remove the blood clot from the vein
  • In rare cases, a healthcare provider may implant a small filter device in the largest vein in the body (the inferior vena cava) to prevent blood clots from reaching the lungs

These more invasive treatments are typically reserved for individuals who cannot tolerate or do not respond well to anticoagulant medications.

Preventing DVT

Given the potentially serious consequences of deep vein thrombosis, it is essential to take proactive steps to reduce your risk of developing this condition. Here are some key ways to prevent DVT:

Maintain an active lifestyle

Regular physical activity and movement can help improve blood flow and reduce the risk of clot formation. If you are required to sit for long periods, such as during air travel or while working at a desk, make sure to take regular breaks to walk around and exercise your leg muscles.

Stay hydrated

Dehydration can increase the risk of blood clots, so it’s important to drink plenty of fluids, especially during extended periods of inactivity or travel.

Wear compression stockings

As mentioned earlier, compression stockings can help improve blood flow and reduce the risk of DVT, particularly for individuals who are at a higher risk, such as those undergoing surgery or individuals with extended periods of immobility.

Manage underlying medical conditions

Conditions like cancer, heart disease, high blood pressure and inherited blood clotting disorders can increase the risk of DVT. Maintaining proper management and treatment of these conditions can help lower your chances of developing a blood clot.

Avoid smoking and maintain a healthy weight

Smoking and obesity are both significant risk factors for deep vein thrombosis. Quitting smoking and achieving a healthy body weight can significantly reduce your risk of developing DVT.

Be proactive during hospitalization and travel

If you are scheduled for surgery or will be spending an extended period in the hospital, be sure to discuss DVT prevention strategies with your healthcare provider. They may recommend the use of compression stockings, anticoagulant medications, or other preventive measures during your stay.

Similarly, if you will be traveling for an extended period, either by plane, train, or car, take steps to keep your legs active and maintain proper hydration to reduce your risk of DVT.

Recognizing a pulmonary embolism

As previously mentioned, the most serious complication of deep vein thrombosis is the development of a pulmonary embolism (PE). A pulmonary embolism occurs when a blood clot breaks free from a DVT and travels to the lungs, blocking blood flow and potentially causing life-threatening consequences.

Symptoms of a pulmonary embolism

The symptoms of a pulmonary embolism can include:

  • Sudden shortness of breath
  • Chest pain, particularly when taking a deep breath
  • Rapid heartbeat
  • Coughing up blood
  • Lightheadedness or fainting

If you or someone you know experiences these symptoms, it is crucial to seek immediate medical attention, as a pulmonary embolism is a medical emergency that requires prompt treatment.

Responding to a pulmonary embolism

If you suspect that someone is experiencing a pulmonary embolism, call the emergency services immediately. While waiting for medical assistance, you can take the following steps:

  • Encourage the person to sit or lie down and try to remain calm
  • Monitor their breathing and provide rescue breaths if necessary
  • If the person becomes unconscious, begin CPR (cardiopulmonary resuscitation) immediately

Prompt recognition and response to the signs of a pulmonary embolism can be the difference between life and death, so it is crucial to be prepared and act quickly in such a situation.

Complications of DVT

While the immediate dangers of deep vein thrombosis, such as a pulmonary embolism, are well-known, the condition can also lead to long-term complications that can significantly impact a person’s quality of life.

Post-thrombotic syndrome

One of the most common long-term complications of DVT is a condition called post-thrombotic syndrome (PTS). PTS occurs when the damage caused by the blood clot to the valves and inner lining of the veins leads to chronic leg pain, swelling, discoloration, and even the development of venous ulcers.

Symptoms of post-thrombotic syndrome can include:

  • Persistent leg swelling
  • Leg pain or heaviness
  • Skin discoloration or reddish-brown pigmentation
  • Varicose veins
  • Venous ulcers

Approximately 20-50% of individuals who experience a DVT will develop post-thrombotic syndrome. The condition can persist for months or even years after the initial clot.

Recurrent DVT

Individuals who have had a DVT are at an increased risk of experiencing a recurrent episode. In fact, studies have shown that up to 30% of people who have had a DVT will develop another one within 10 years.

The risk of recurrence is particularly high in the first few months after the initial clot, highlighting the importance of adhering to the prescribed treatment plan and maintaining regular follow-ups with a healthcare provider.

Treatment of DVT

Receiving a diagnosis of deep vein thrombosis can be a stressful and overwhelming experience. However, with the right support and strategies, individuals can effectively manage their condition and minimize the impact on their daily lives.

Medication management

Strict adherence to the prescribed anticoagulant medication regimen is crucial for the successful treatment of DVT. Patients should work closely with their healthcare providers to ensure they are taking the correct dosage and attending all necessary follow-up appointments for blood tests and monitoring.

Lifestyle adjustments

Incorporating lifestyle changes, such as regular exercise, maintaining a healthy weight, and staying hydrated, can help mitigate the symptoms of DVT and reduce the risk of recurrence.

Emotional support

The physical and emotional impact of a DVT diagnosis can be significant. Seeking support from family, friends, or a mental health professional can help individuals cope with the stress and anxiety associated with the condition.

Ongoing monitoring and follow-up

Regular check-ups with a healthcare provider are essential for monitoring the progress of the DVT and ensuring that any long-term complications are detected and addressed promptly.

By taking an active role in their treatment and recovery, individuals with deep vein thrombosis can effectively manage their condition and minimize the risks of potentially life-threatening complications.


Deep vein thrombosis is a serious medical condition that requires prompt diagnosis and treatment to prevent potentially life-threatening complications, such as a pulmonary embolism. By understanding the symptoms, risk factors, and prevention strategies, you can take proactive steps to reduce your chances of developing DVT.

If you experience any symptoms of deep vein thrombosis or a pulmonary embolism, you should seek immediate medical attention. Early detection and proper management can make all the difference in ensuring a positive outcome and preventing long-term complications. Stay vigilant, prioritize your health, and don’t hesitate to speak to your healthcare provider if needed.


Medical Disclaimer

NowPatient has taken all reasonable steps to ensure that all material is factually accurate, complete, and current. However, the knowledge and experience of a qualified healthcare professional should always be sought after instead of using the information in this page. Before taking any drug, you should always speak to your doctor or another qualified healthcare provider.

The information provided here about medications is subject to change and is not meant to include all uses, precautions, warnings, directions, drug interactions, allergic reactions, or negative effects. The absence of warnings or other information for a particular medication does not imply that the medication or medication combination is appropriate for all patients or for all possible purposes.

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